I have a developer unlocked Lumia 635 just yesterday updated to Windows 10 Mobile Technical Preview (OS version: 10.0.12562.84).
After
I just faced the same problem described by @Sevenate.
Following the response of @user4855870 I'm finally able to deploy my blank Universal App to my Lumia 520 running W10 TP.
1) On the phone, go to Settings, System, About, More Info and write down the OS version (in my case it is 10.0.12534.59);
2) On Visual Studio, open Package.appxmanifest and in the same line mentioned by @user4855870 on the "MinVersion" write "10.0.1.0" and on the "MaxVersionTested" write the OS version you got from your phone.
My blank Universal App works on computer and phone as it should ;)